What's the battery health of this car? In a world where electric cars become commonplace, this will be the first question to ask when buying a second-hand car. However, without reliable and comparable indicators, getting a reliable answer on the 'state of health' of used batteries will be difficult. A crucial milestone on the road to European standards for sustainable batteries has been achieved: CEN and CENELEC accepted the European Commission's standardisation request for new definitions and technical specifications - one small step towards decarbonised mobility.